Many types of window coverings are currently available including window shades, venetian blinds, louver blinds, mini-blinds and pleated shades. Until recent years all of these coverings were sold in either stock widths in retail outlets, such as mass merchandisers, in which event the coat per covering was quite low, or were sold as a customized product, usually at specialty stores, in which event the cost was quite high on a per unit basis.
The disadvantage of being limited to a choice of only a few stock widths is that many windows, particularly windows in older homes, are of non-standard widths. Hence, if a stock width covering was too wide for the window, it had to be mounted on the outside of the window frame which generally is aesthetically unpleasing and may present decorating difficulties if drapes were also desired in addition to the standard window covering. If the stock width covering was not quite wide enough to cover the complete window width, light could enter along the edges and privacy was not complete.
The above described disadvantages of the stock width coverings were overcome by customized coverings, such as those which are provided by specialty stores, but customized coverings are so expensive that they were, and are, unavailable to the great mass of potential purchasers due to their high per unit cost.
The disadvantage of some of the stock width coverings have been overcome to a considerable extent by the development in recent years of size-at-home or size-in-store window coverings. For example, a window shade has been developed which the purchaser can buy in a mass merchandising retail outlet on an impulse; i.e., not a planned purchase, take home and size to the exact width required at the point of, and the moment of, installation. More recently a system for sizing mini-blinds in a retail outlet such as a mass merchandiser using the level of skill typically found in such establishments has been developed.
However, no size-in-store system has been known for sizing pleated blinds to an exact required width at the point of purchase in retail outlets, including mass merchandisers, utilizing the skill level of the service personnel which are typically found in such retail establishments. One physical limitation which is generally characteristic of pleated blinds as contrasted to, for example, mini-blinds, is that the pleated blinds available at the present time require that the lift cords by which the bottom rail, and the pleats thereabove, are moved toward and away from the head rail must be fixed in location at the factory, thus necessitating that shortening be done at each end of the pleats to preserve the aesthetically balanced appearance of the covering. However, the head rail can only be shortened at one end due to the arrangement of the cord raising, lowering, and locking mechanism which is hidden from view at one end of the head rail and accessed only through the side of the head rail at one end thereof, thus precluding the possibility of concurrent sizing of pleats and rails. This limitation should be contrasted to the recent system for sizing mini-blinds referred to earlier in which the sizing is simply and easily accomplished by moving one or more ladder and lift cords toward the cord lock end of the structure and sizing all elements in one operation, followed by replacement of the earlier displaced ladder and lift elements to their sized, final positions. This procedure is not feasible for pleated shades in which the lift cords are fixed in position at the factory.